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1.
bioRxiv ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38585903

RESUMO

GABAergic interneuron deficits have been implicated in the epileptogenesis of multiple neurological diseases. While epileptic seizures are a key clinical hallmark of CLN2 disease, a childhood-onset neurodegenerative lysosomal storage disorder caused by a deficiency of tripeptidyl peptidase 1 (TPP1), the etiology of these seizures remains elusive. Given that Cln2 R207X/R207X mice display fatal spontaneous seizures and an early loss of several cortical interneuron populations, we hypothesized that those two events might be causally related. To address this hypothesis, we first generated an inducible transgenic mouse expressing lysosomal membrane-tethered TPP1 (TPP1LAMP1) on the Cln2 R207X/R207X genetic background to study the cell-autonomous effects of cell-type-specific TPP1 deficiency. We crossed the TPP1LAMP1 mice with Vgat-Cre mice to introduce interneuron-specific TPP1 deficiency. Vgat-Cre ; TPP1LAMP1 mice displayed storage material accumulation in several interneuron populations both in cortex and striatum, and increased susceptibility to die after PTZ-induced seizures. Secondly, to test the role of GABAergic interneuron activity in seizure progression, we selectively activated these cells in Cln2 R207X/R207X mice using Designer Receptor Exclusively Activated by Designer Drugs (DREADDs) in in Vgat-Cre : Cln2 R207X/R207X mice. EEG monitoring revealed that DREADD-mediated activation of interneurons via chronic deschloroclozapine administration accelerated the onset of spontaneous seizures and seizure-associated death in Vgat-Cre : Cln2 R207X/R207X mice, suggesting that modulating interneuron activity can exert influence over epileptiform abnormalities in CLN2 disease. Taken together, these results provide new mechanistic insights into the underlying etiology of seizures and premature death that characterize CLN2 disease.

2.
bioRxiv ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38352351

RESUMO

Numerous studies have identified dopamine signaling in the hippocampus as necessary for certain types of learning and memory. Since dopamine in the striatum is strongly tied to rewards, dopamine in the hippocampus is thought to reinforce reward learning. Despite the critical influence of dopamine on hippocampal function, little is known about dopamine release in the hippocampus or the specific ways dopamine can influence hippocampal function. Based on the functional complexity of hippocampal circuitry, we hypothesized the existence of multiple dopamine signaling domains. Using optical dopamine sensors, two-photon imaging, and head-fixed behaviors, we identified two functionally and spatially distinct dopamine domains in the hippocampus. The "superficial" domain (cell somata and apical dendrites) showed reward-related dopamine transients early in Pavlovian conditioning but were replaced by "deep" domain transients (basal dendritic layer) with experience. These two domains also play distinct roles in a hippocampal-dependent, goal-directed virtual reality task where mice use exploratory licks to discover the location of a hidden reward zone. Here, positive dopamine ramps appeared in the superficial domain as mice approached the reward zone, similar to those seen in the striatum. At the same time, the deep domain showed strong reward-related transients. These results reveal small-scale, anatomically segregated, dopamine domains in the hippocampus. Furthermore dopamine domain activity had temporal-specificity for different phases of behavior. Finally, the subcellular scale of dopamine domains suggests specialized postsynaptic pathways for processing and integrating functionally distinct dopaminergic influences.

3.
Methods Mol Biol ; 2748: 135-149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38070113

RESUMO

The functional fitness of CAR T cells plays a crucial role in determining their clinical efficacy. Several strategies are being explored to increase cellular fitness, but screening these approaches in vivo is expensive and time-consuming, limiting the number of strategies that can be tested at one time. The presence of polyfunctional CAR T cells has emerged as a critical parameter correlating with clinical responses. However, even sophisticated multiplexed secretomic assays often fail to detect differences in cytokine release due to the functional heterogeneity of CAR T cell products. Here, we describe a highly multiplexed single-cell secretomic assay based on the IsoLight platform to rapidly evaluate the impact of new pharmacologic or gene-engineering approaches aiming at improving CAR T cell function. As a key study, we focus on CD19-specific CAR CD8+ T cells modulated by miR-155 overexpression, but the protocol can be applied to characterize other functional immune cell modulation strategies.


Assuntos
Linfócitos T CD8-Positivos , Receptores de Antígenos de Linfócitos T , Resultado do Tratamento , Antígenos CD19 , Imunoterapia Adotiva/métodos
4.
Science ; 382(6676): 1270-1276, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38096385

RESUMO

Current HIV vaccines designed to stimulate CD8+ T cells have failed to induce immunologic control upon infection. The functions of vaccine-induced HIV-specific CD8+ T cells were investigated here in detail. Cytotoxic capacity was significantly lower than in HIV controllers and was not a consequence of low frequency or unaccumulated functional cytotoxic proteins. Low cytotoxic capacity was attributable to impaired degranulation in response to the low antigen levels present on HIV-infected targets. The vaccine-induced T cell receptor (TCR) repertoire was polyclonal and transduction of these TCRs conferred the same reduced functions. These results define a mechanism accounting for poor antiviral activity induced by these vaccines and suggest that an effective CD8+ T cell response may require a vaccination strategy that drives further TCR clonal selection.


Assuntos
Vacinas contra a AIDS , Degranulação Celular , Citotoxicidade Imunológica , Infecções por HIV , Linfócitos T Citotóxicos , Humanos , Vacinas contra a AIDS/imunologia , Células Clonais , Infecções por HIV/prevenção & controle , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Degranulação Celular/imunologia
5.
Proteomics ; 23(13-14): e2200242, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36786585

RESUMO

Genetically and phenotypically identical immune cell populations can be highly heterogenous in terms of their immune functions and protein secretion profiles. The microfluidic chip-based single-cell highly multiplexed secretome proteomics enables characterization of cellular heterogeneity of immune responses at different cellular and molecular layers. Increasing evidence has demonstrated that polyfunctional T cells that simultaneously produce 2+ proteins per cell at the single-cell level are key effector cells that contribute to the development of potent and durable cellular immunity against pathogens and cancers. The functional proteomic technology offers a wide spectrum of cellular function assessment and can uniquely define highly polyfunctional cell subsets with cytokine signatures from live individual cells. This high-dimensional single-cell analysis provides deep dissection into functional heterogeneity and helps identify predictive biomarkers and potential correlates that are crucial for immunotherapeutic product design optimization and personalized immunotherapy development to achieve better clinical outcomes.


Assuntos
Proteômica , Secretoma , Citocinas , Linfócitos T , Imunoterapia , Análise de Célula Única
6.
J Tissue Eng ; 12: 20417314211027714, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262686

RESUMO

Transplantation of pancreatic islets has been shown to be effective, in some patients, for the long-term treatment of type 1 diabetes. However, transplantation of islets into either the portal vein or the subcutaneous space can be limited by insufficient oxygen transfer, leading to islet loss. Furthermore, oxygen diffusion limitations can be magnified when islet numbers are increased dramatically, as in translating from rodent studies to human-scale treatments. To address these limitations, an islet transplantation approach using an acellular vascular graft as a vascular scaffold has been developed, termed the BioVascular Pancreas (BVP). To create the BVP, islets are seeded as an outer coating on the surface of an acellular vascular graft, using fibrin as a hydrogel carrier. The BVP can then be anastomosed as an arterial (or arteriovenous) graft, which allows fully oxygenated arterial blood with a pO2 of roughly 100 mmHg to flow through the graft lumen and thereby supply oxygen to the islets. In silico simulations and in vitro bioreactor experiments show that the BVP design provides adequate survivability for islets and helps avoid islet hypoxia. When implanted as end-to-end abdominal aorta grafts in nude rats, BVPs were able to restore near-normoglycemia durably for 90 days and developed robust microvascular infiltration from the host. Furthermore, pilot implantations in pigs were performed, which demonstrated the scalability of the technology. Given the potential benefits provided by the BVP, this tissue design may eventually serve as a solution for transplantation of pancreatic islets to treat or cure type 1 diabetes.

7.
NPJ Regen Med ; 6(1): 40, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326344

RESUMO

A significant barrier to implementation of cell-based therapies is providing adequate vascularization to provide oxygen and nutrients. Here we describe an approach for cell transplantation termed the Therapeutic Vascular Conduit (TVC), which uses an acellular vessel as a scaffold for a hydrogel sheath containing cells designed to secrete a therapeutic protein. The TVC can be directly anastomosed as a vascular graft. Modeling supports the concept that the TVC allows oxygenated blood to flow in close proximity to the transplanted cells to prevent hypoxia. As a proof-of-principle study, we used erythropoietin (EPO) as a model therapeutic protein. If implanted as an arteriovenous vascular graft, such a construct could serve a dual role as an EPO delivery platform and hemodialysis access for patients with end-stage renal disease. When implanted into nude rats, TVCs containing EPO-secreting fibroblasts were able to increase serum EPO and hemoglobin levels for up to 4 weeks. However, constitutive EPO expression resulted in macrophage infiltration and luminal obstruction of the TVC, thus limiting longer-term efficacy. Follow-up in vitro studies support the hypothesis that EPO also functions to recruit macrophages. The TVC is a promising approach to cell-based therapeutic delivery that has the potential to overcome the oxygenation barrier to large-scale cellular implantation and could thus be used for a myriad of clinical disorders. However, a complete understanding of the biological effects of the selected therapeutic is absolutely essential.

8.
Proc Natl Acad Sci U S A ; 117(49): 31177-31188, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33219123

RESUMO

A transplanted stem cell's engagement with a pathologic niche is the first step in its restoring homeostasis to that site. Inflammatory chemokines are constitutively produced in such a niche; their binding to receptors on the stem cell helps direct that cell's "pathotropism." Neural stem cells (NSCs), which express CXCR4, migrate to sites of CNS injury or degeneration in part because astrocytes and vasculature produce the inflammatory chemokine CXCL12. Binding of CXCL12 to CXCR4 (a G protein-coupled receptor, GPCR) triggers repair processes within the NSC. Although a tool directing NSCs to where needed has been long-sought, one would not inject this chemokine in vivo because undesirable inflammation also follows CXCL12-CXCR4 coupling. Alternatively, we chemically "mutated" CXCL12, creating a CXCR4 agonist that contained a strong pure binding motif linked to a signaling motif devoid of sequences responsible for synthetic functions. This synthetic dual-moity CXCR4 agonist not only elicited more extensive and persistent human NSC migration and distribution than did native CXCL 12, but induced no host inflammation (or other adverse effects); rather, there was predominantly reparative gene expression. When co-administered with transplanted human induced pluripotent stem cell-derived hNSCs in a mouse model of a prototypical neurodegenerative disease, the agonist enhanced migration, dissemination, and integration of donor-derived cells into the diseased cerebral cortex (including as electrophysiologically-active cortical neurons) where their secreted cross-corrective enzyme mediated a therapeutic impact unachieved by cells alone. Such a "designer" cytokine receptor-agonist peptide illustrates that treatments can be controlled and optimized by exploiting fundamental stem cell properties (e.g., "inflammo-attraction").


Assuntos
Quimiocina CXCL12/genética , Neurônios/metabolismo , Ligação Proteica/genética , Receptores CXCR4/genética , Astrócitos/metabolismo , Astrócitos/patologia , Movimento Celular/genética , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Humanos , Células-Tronco Pluripotentes Induzidas , Inflamação/genética , Ligantes , Mutagênese/genética , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/transplante , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/terapia , Neurônios/patologia
9.
Foot Ankle Orthop ; 5(3): 2473011420931419, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35097390

RESUMO

BACKGROUND: As the movement toward evidence-based medicine grows and publication rates rise each year, critical analysis of the orthopedic literature has become increasingly important. To aid readers in assessing the scientific quality of published research, Foot & Ankle International (FAI) began assigning levels of evidence to all clinical articles in 2008. The purpose of this study was to analyze trends in the characteristics and levels of evidence of articles published in FAI between 2000 and 2015. METHODS: All articles published in FAI from the years 2000, 2005, 2010, and 2015 were reviewed and categorized into article type (clinical, basic science, review, or technical tip). Each clinical article was assigned a level of evidence (I-V) and study type (prognostic, therapeutic, economic, or diagnostic). Descriptive information was gathered pertaining to country of origin, author credentials, and funding. Statistical analysis was performed using chi-squared tests to detect any trends in levels of evidence and publication characteristics. RESULTS: A total of 647 articles were reviewed. From 2000 to 2015, there was a statistically significant increase in the publication of clinical research articles (70% to 83%; P = .013), while the number of basic science articles decreased (29% to 17%; P = .013). Of the clinical articles, there was a significant increase in therapeutic studies (41% to 58%; P = .003). During the study period, the publication of Level I and II evidence significantly increased (2% to 14%; P = .002). Although Level III and V evidence also increased (65% to 71%, P > .99), this was not found to be statistically significant. Publications originated from a total of 39 countries, with a significant increase in the proportion of international papers (33% to 48%; P = .007) over the study period. The proportion of articles authored by Doctors of Podiatric Medicine (DPMs) during the study period significantly decreased (4% to 2%, P = .035). Finally, the percentage of studies that disclosed the use of outside funding increased during the study period, with reported funding from grants or professional groups rising from 3% to 16% (P < .001) and reported funding from commercial sources rising from 0% to 9% (P = .002). CONCLUSION: The proportion of Level I and II studies published in FAI significantly increased from 2000 to 2015. The publication of clinical research rose, with a majority being therapeutic studies. There was a significant increase in articles published by international authors and a significant decrease in articles published by DPMs. During the same time period, there was a rise in the proportion of articles reporting the use of outside funding, both professional and commercial.

10.
Tissue Eng Part A ; 26(9-10): 556-568, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31724494

RESUMO

The pancreatic islet is a highly vascularized micro-organ, and rapid revascularization postislet transplantation is important for islet survival and function. However, the various mechanisms involved in islet revascularization are not fully understood, and we currently lack good in vitro platforms to explore this. Our aim for this study was to generate perfusable microvascular networks in a microfluidic chip device, in which islets could be easily integrated, to establish an in vitro platform for investigations on islet-microvasculature interactions. We compared the ability of mesenchymal stem cells (MSCs) and fibroblasts to support microvascular network formation by human umbilical vein endothelial cells (HUVECs) and human induced pluripotent stem cell-derived endothelial colony-forming cell in two-dimensional and three-dimensional models of angiogenesis, and tested the effect of different culture media on microvessel formation. HUVECs that were supported by MSCs formed patent and perfusable networks in a fibrin gel, whereas networks supported by fibroblasts rapidly regressed. Network morphology could be controlled by adjusting relative cell numbers and densities. Incorporation of isolated rat islets demonstrated that islets recruit local microvasculature in vitro, but that the microvessels did not invade islets, at least during the course of these studies. This in vitro microvascularization platform can provide a useful tool to study how various parameters affect islet integration with microvascular networks and could also be utilized for studies of vascularization of other organ systems. Impact statement To improve pancreatic islet graft survival and function posttransplantation, rapid and adequate revascularization is critical. Efforts to improve islet revascularization are demanding due to an insufficient understanding of the mechanisms involved in the process. We have applied a microfluidics platform to generate microvascular networks, and by incorporating pancreatic islets, we were able to study microvasculature-islet interactions in real time. This platform can provide a useful tool to study islet integration with microvascular networks, and could be utilized for studies of vascularization of other organ systems. Moreover, this work may be adapted toward developing a prevascularized islet construct for transplantation.


Assuntos
Ilhotas Pancreáticas/citologia , Células-Tronco Mesenquimais/citologia , Animais , Células Cultivadas , Feminino , Fibrina/química , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Ratos
11.
Elife ; 82019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31591960

RESUMO

Inhibition plays a powerful role in regulating network excitation and plasticity; however, the activity of defined interneuron types during spatial exploration remain poorly understood. Using two-photon calcium imaging, we recorded hippocampal CA1 somatostatin- and parvalbumin-expressing interneurons as mice performed a goal-directed spatial navigation task in new visual virtual reality (VR) contexts. Activity in both interneuron classes was strongly suppressed but recovered as animals learned to adapt the previously learned task to the new spatial context. Surprisingly, although there was a range of activity suppression across the population, individual somatostatin-expressing interneurons showed consistent levels of activity modulation across exposure to multiple novel environments, suggesting context-independent, stable network roles during spatial exploration. This work reveals population-level temporally dynamic interneuron activity in new environments, within which each interneuron shows stable and consistent activity modulation.


Assuntos
Interneurônios/fisiologia , Realidade Virtual , Animais , Cálcio/metabolismo , Interneurônios/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
12.
Adv Sci (Weinh) ; 6(8): 1801531, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-31016107

RESUMO

The perivascular niche (PVN) plays an essential role in brain tumor stem-like cell (BTSC) fate control, tumor invasion, and therapeutic resistance. Here, a microvasculature-on-a-chip system as a PVN model is used to evaluate the ex vivo dynamics of BTSCs from ten glioblastoma patients. BTSCs are found to preferentially localize in the perivascular zone, where they exhibit either the lowest motility, as in quiescent cells, or the highest motility, as in the invasive phenotype, with migration over long distance. These results indicate that PVN is a niche for BTSCs, while the microvascular tracks may serve as a path for tumor cell migration. The degree of colocalization between tumor cells and microvessels varies significantly across patients. To validate these results, single-cell transcriptome sequencing (10 patients and 21 750 single cells in total) is performed to identify tumor cell subtypes. The colocalization coefficient is found to positively correlate with proneural (stem-like) or mesenchymal (invasive) but not classical (proliferative) tumor cells. Furthermore, a gene signature profile including PDGFRA correlates strongly with the "homing" of tumor cells to the PVN. These findings demonstrate that the model can recapitulate in vivo tumor cell dynamics and heterogeneity, representing a new route to study patient-specific tumor cell functions.

13.
J Med Chem ; 61(8): 3516-3540, 2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29526098

RESUMO

Dysregulated translation of mRNA plays a major role in tumorigenesis. Mitogen-activated protein kinase interacting kinases (MNK)1/2 are key regulators of mRNA translation integrating signals from oncogenic and immune signaling pathways through phosphorylation of eIF4E and other mRNA binding proteins. Modulation of these key effector proteins regulates mRNA, which controls tumor/stromal cell signaling. Compound 23 (eFT508), an exquisitely selective, potent dual MNK1/2 inhibitor, was designed to assess the potential for control of oncogene signaling at the level of mRNA translation. The crystal structure-guided design leverages stereoelectronic interactions unique to MNK culminating in a novel pyridone-aminal structure described for the first time in the kinase literature. Compound 23 has potent in vivo antitumor activity in models of diffuse large cell B-cell lymphoma and solid tumors, suggesting that controlling dysregulated translation has real therapeutic potential. Compound 23 is currently being evaluated in Phase 2 clinical trials in solid tumors and lymphoma. Compound 23 is the first highly selective dual MNK inhibitor targeting dysregulated translation being assessed clinically.


Assuntos
Antineoplásicos/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/uso terapêutico , Piridonas/uso terapêutico , Pirimidinas/uso terapêutico , Compostos de Espiro/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Domínio Catalítico , Linhagem Celular Tumoral , Desenho de Fármacos , Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação 4E em Eucariotos/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Estrutura Molecular , Fosforilação , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Piridinas/síntese química , Piridinas/química , Piridinas/farmacologia , Piridonas/síntese química , Piridonas/química , Piridonas/farmacologia , Pirimidinas/síntese química , Pirimidinas/química , Pirimidinas/farmacologia , Ratos , Serina/química , Transdução de Sinais/efeitos dos fármacos , Compostos de Espiro/síntese química , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Cell Transplant ; 26(8): 1365-1379, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28901188

RESUMO

In this study, we used a polydimethylsiloxane (PDMS)-based platform for the generation of intact, perfusion-competent microvascular networks in vitro. COMSOL Multiphysics, a finite-element analysis and simulation software package, was used to obtain simulated velocity, pressure, and shear stress profiles. Transgene-free human induced pluripotent stem cells (hiPSCs) were differentiated into partially arterialized endothelial cells (hiPSC-ECs) in 5 d under completely chemically defined conditions, using the small molecule glycogen synthase kinase 3ß inhibitor CHIR99021 and were thoroughly characterized for functionality and arterial-like marker expression. These cells, along with primary human umbilical vein endothelial cells (HUVECs), were seeded in the PDMS system to generate microvascular networks that were subjected to shear stress. Engineered microvessels had patent lumens and expressed VE-cadherin along their periphery. Shear stress caused by flowing medium increased the secretion of nitric oxide and caused endothelial cells s to align and to redistribute actin filaments parallel to the direction of the laminar flow. Shear stress also caused significant increases in gene expression for arterial markers Notch1 and EphrinB2 as well as antithrombotic markers Kruppel-like factor 2 (KLF-2)/4. These changes in response to shear stress in the microvascular platform were observed in hiPSC-EC microvessels but not in microvessels that were derived from HUVECs, which indicated that hiPSC-ECs may be more plastic in modulating their phenotype under flow than are HUVECs. Taken together, we demonstrate the feasibly of generating intact, engineered microvessels in vitro, which replicate some of the key biological features of native microvessels.


Assuntos
Dimetilpolisiloxanos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular , Células Endoteliais , Humanos , Imuno-Histoquímica
15.
J Neurosci ; 37(38): 9222-9238, 2017 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-28842418

RESUMO

Network activity is strongly tied to animal movement; however, hippocampal circuits selectively engaged during locomotion or immobility remain poorly characterized. Here we examined whether distinct locomotor states are encoded differentially in genetically defined classes of hippocampal interneurons. To characterize the relationship between interneuron activity and movement, we used in vivo, two-photon calcium imaging in CA1 of male and female mice, as animals performed a virtual-reality (VR) track running task. We found that activity in most somatostatin-expressing and parvalbumin-expressing interneurons positively correlated with locomotion. Surprisingly, nearly one in five somatostatin or one in seven parvalbumin interneurons were inhibited during locomotion and activated during periods of immobility. Anatomically, the somata of somatostatin immobility-activated neurons were smaller than those of movement-activated neurons. Furthermore, immobility-activated interneurons were distributed across cell layers, with somatostatin-expressing cells predominantly in stratum oriens and parvalbumin-expressing cells mostly in stratum pyramidale. Importantly, each cell's correlation between activity and movement was stable both over time and across VR environments. Our findings suggest that hippocampal interneuronal microcircuits are preferentially active during either movement or immobility periods. These inhibitory networks may regulate information flow in "labeled lines" within the hippocampus to process information during distinct behavioral states.SIGNIFICANCE STATEMENT The hippocampus is required for learning and memory. Movement controls network activity in the hippocampus but it's unclear how hippocampal neurons encode movement state. We investigated neural circuits active during locomotion and immobility and found interneurons were selectively active during movement or stopped periods, but not both. Each cell's response to locomotion was consistent across time and environments, suggesting there are separate dedicated circuits for processing information during locomotion and immobility. Understanding how the hippocampus switches between different network configurations may lead to therapeutic approaches to hippocampal-dependent dysfunctions, such as Alzheimer's disease or cognitive decline.


Assuntos
Hipocampo/fisiologia , Interneurônios/fisiologia , Locomoção/fisiologia , Rede Nervosa/fisiologia , Inibição Neural/fisiologia , Animais , Geradores de Padrão Central/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Descanso/fisiologia
16.
Clin Cancer Res ; 23(4): 992-1000, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27573171

RESUMO

Purpose: Despite the importance of the MET oncogene in many malignancies, clinical strategies targeting c-Met have benefitted only small subsets of patients with tumors driven by signaling through the c-Met pathway, thereby necessitating selection of patients with MET amplification and/or c-Met activation most likely to respond. An ADC targeting c-Met could overcome these limitations with potential as a broad-acting therapeutic.Experimental Design: ADC ABBV-399 was generated with the c-Met-targeting antibody, ABT-700. Antitumor activity was evaluated in cancer cells with overexpressed c-Met or amplified MET and in xenografts including patient-derived xenograft (PDX) models and those refractory to other c-Met inhibitors. The correlation between c-Met expression and sensitivity to ABBV-399 in tumor and normal cell lines was assessed to evaluate the risk of on-target toxicity.Results: A threshold level of c-Met expressed by sensitive tumor but not normal cells is required for significant ABBV-399-mediated killing of tumor cells. Activity extends to c-Met or amplified MET cell line and PDX models where significant tumor growth inhibition and regressions are observed. ABBV-399 inhibits growth of xenograft tumors refractory to other c-Met inhibitors and provides significant therapeutic benefit in combination with standard-of-care chemotherapy.Conclusions: ABBV-399 represents a novel therapeutic strategy to deliver a potent cytotoxin to c-Met-overexpressing tumor cells enabling cell killing regardless of reliance on MET signaling. ABBV-399 has progressed to a phase I study where it has been well tolerated and has produced objective responses in c-Met-expressing non-small cell lung cancer (NSCLC) patients. Clin Cancer Res; 23(4); 992-1000. ©2016 AACR.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Proto-Oncogênicas c-met/genética , Animais , Anticorpos Monoclonais/efeitos adversos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Neoplasias/imunologia , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Biomaterials ; 91: 140-150, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27019026

RESUMO

Despite considerable advances in prostate cancer research, there is a major need for a systemic delivery platform that efficiently targets anti-cancer drugs to sites of disseminated prostate cancer while minimizing host toxicity. In this proof-of-principle study, human mesenchymal stem cells (MSCs) were loaded with poly(lactic-co-glycolic acid) (PLGA) microparticles (MPs) that encapsulate the macromolecule G114, a thapsigargin-based prostate specific antigen (PSA)-activated prodrug. G114-particles (∼950 nm in size) were internalized by MSCs, followed by the release of G114 as an intact prodrug from loaded cells. Moreover, G114 released from G114 MP-loaded MSCs selectively induced death of the PSA-secreting PCa cell line, LNCaP. Finally, G114 MP-loaded MSCs inhibited tumor growth when used in proof-of-concept co-inoculation studies with CWR22 PCa xenografts, suggesting that cell-based delivery of G114 did not compromise the potency of this pro-drug in-vitro or in-vivo. This study demonstrates a potentially promising approach to assemble a cell-based drug delivery platform, which inhibits cancer growth in-vivo without the need of genetic engineering. We envision that upon achieving efficient homing of systemically infused MSCs to cancer sites, this MSC-based platform may be developed into an effective, systemic 'Trojan Horse' therapy for targeted delivery of therapeutic agents to sites of metastatic PCa.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Transplante de Células-Tronco Mesenquimais , Pró-Fármacos/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Ácido Láctico/química , Masculino , Células-Tronco Mesenquimais/citologia , Camundongos Nus , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Pró-Fármacos/uso terapêutico , Próstata/efeitos dos fármacos , Próstata/metabolismo , Próstata/patologia , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
18.
J Clin Psychopharmacol ; 36(2): 169-72, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26859276

RESUMO

BACKGROUND: Antipsychotic-associated acute pancreatitis presents like pancreatitis from other causes, requiring clinical judgment, tests, and decision support to establish the diagnosis. Many new cases of atypical antipsychotic pancreatitis have been established, and current decision supports are out of date as antipsychotic polypharmacy is being recognized. Given the population frequency of psychosis and frequency of antipsychotic prescribing, we reviewed published cases summarizing common clinical findings and antipsychotics associated with acute pancreatitis to updating earlier decision support. METHODS: Case reports of antipsychotic pancreatitis from 1990 to 2015 were reviewed and abstracted by independent reviewers. Demographic, clinical features, management, and Naranjo and probability scores were abstracted and reviewed for associations. Appropriate statistical tests were selected for normally and non-normally distributed data. RESULTS: We summarized 41 cases of acute pancreatitis associated with antipsychotics, and cases were younger men (59%) (mean age, 39 years). Alcohol, diabetes, and previous lithiasis appeared in 27%; polypharmacy was associated with 53% of cases, and 80% had concomitant use of other medication linked to pancreatitis.The median lipase, amylase, and alkaline phosphate during acute presentation were 1210 IU/L (range, 243-5482 IU/L), 492 IU/L (range, 3-2916 IU/L), and 152 IU/L (range, 119-367 IU/L), respectively. Median exposure to antipsychotics were 49 days (range, 5-3,650 days); most were mild (63%, n = 26), several severe (27%, n = 11), and few fatal (10%, n = 4). DISCUSSION: We identified 41 reports of antipsychotic-related acute pancreatitis, many associated with antipsychotic polypharmacy. Olanzapine, risperidone, quetiapine, aripiprazole, and ziprasidone are associated with acute pancreatitis and often in combination with mood stabilizers.


Assuntos
Antipsicóticos/efeitos adversos , Pancreatite/induzido quimicamente , Pancreatite/diagnóstico , Polimedicação , Adolescente , Adulto , Idoso , Criança , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Pancreatite/epidemiologia , Esquizofrenia/diagnóstico , Esquizofrenia/tratamento farmacológico , Esquizofrenia/epidemiologia , Resultado do Tratamento , Adulto Jovem
19.
Adv Healthc Mater ; 5(1): 10-55, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25772134

RESUMO

Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer.


Assuntos
Tecnologia Biomédica/métodos , Células-Tronco/citologia , Engenharia Tecidual/métodos , Animais , Terapia Genética , Humanos , Neoplasias/terapia , Regeneração
20.
Cell Rep ; 10(8): 1261-1268, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25732817

RESUMO

Poor homing of systemically infused cells to disease sites may limit the success of exogenous cell-based therapy. In this study, we screened 9,000 signal-transduction modulators to identify hits that increase mesenchymal stromal cell (MSC) surface expression of homing ligands that bind to intercellular adhesion molecule 1 (ICAM-1), such as CD11a. Pretreatment of MSCs with Ro-31-8425, an identified hit from this screen, increased MSC firm adhesion to an ICAM-1-coated substrate in vitro and enabled targeted delivery of systemically administered MSCs to inflamed sites in vivo in a CD11a- (and other ICAM-1-binding domains)-dependent manner. This resulted in a heightened anti-inflammatory response. This represents a new strategy for engineering cell homing to enhance therapeutic efficacy and validates CD11a and ICAM-1 as potential targets. Altogether, this multi-step screening process may significantly improve clinical outcomes of cell-based therapies.


Assuntos
Células-Tronco Mesenquimais/citologia , Bibliotecas de Moléculas Pequenas/química , Animais , Antígeno CD11a/genética , Antígeno CD11a/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular , Ensaios de Triagem em Larga Escala , Humanos , Indóis/química , Indóis/farmacologia , Inflamação/induzido quimicamente , Inflamação/patologia , Inflamação/terapia , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos/toxicidade , Maleimidas/química , Maleimidas/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Regulação para Cima
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